Operating mechanism for the threadcarrier rails of flat framework knitting machines



Nov. 3, 1936. A. LOIMANN 2,059,375

OPERATING MECHANISM FOR THE THREAD CARRIER RAILS 0F FLAT FRAMEWORK KNITTING MACHINES Filed Jan. 14, 1936 2 Sheets-Sheet 1 Fig. 4.

\NVENTOR ANTON LOIMANN ATTONEY Nov. 3, 1936. A. LOIMANN 2,059,375 7 OPERATING MECHANISM FOR THE THREAD CARRIER RAILS 0F FLAT FRAMEWORK KNITTING MACHINES Filed Jan. 14, 1936 2 Sheets-Sheet 2 INVENTOR ANTON LOIMANN Bv W ATTORNEY Patented Nov. 3, 1936 UNITED STATES GPERATING MECHANISM FOR THE THREAD- CARRIER RAILS OF FLAT FRAMEWORK KNITTING MACHINES Anton Loimann, Chemnitz, Germany Application January 14, 1936, Serial No. 59,129

In Germany January 9, 1935 9 Claims.

This invention relates to operating mechanisms for the thread-carrier rails of flat framework knitting machines the catch-bar of said rails being moved by the aid of a flexible driving chain laid around several rollers that are adjustable in longitudinal direction of the machine.

In known constructions of this kind the smallest possible path of motion for the catch-bar for the respective thread-carrier rail is defined by the size of the guide-rollers for the driving chain. This is due to the fact that the ascending part of said chain must always remain at a distance from the descending part said distance being greater than twice the diameter of a guideroller. For this reason the path of motion of the said catch-bar cannot be reduced to an extent, as is for instance possible when knitting the front part or toe portion of a stocking. Thus, in known driving devices for machines of the present kind the so-called brakes which serve for the transmission of motion from the catchbai'lto the thread-carrier rail cannot be dispensed w1 In order to obviate this disadvantage, according to my invention the sprocket-wheels for the driving chains which serve for guiding the latter from the one to the other supporting slide are so displaced with respect to each other that said sprocket-wheels during displacement of said slides into their shortest distance from each other will move past each other or at least come into co-axial position.

In the accompanying drawings which form part of this specification several exemplifications of the construction of the novel operating mechanism are shown, Fig. 1 being an elevation of the improved driving andoperating organs of a flat framework knitting machine provided withthe present mechanism, Figs. 2 and 3 being plan views of several arrangements of sprocketwheels for the machine, Figs. 4 and 5 an elevation and plan view, respectively, showing another arrangement of sprocket-wheels, Fig. 6 a plan view of another novel construction of the operc 45 ating mechanism, and Fig. 7 an explanatory, diagram illustrating the mode of operation of said mechanism.

Referring more particularly to the drawings, the ends of the driving chain 4 having one or more tracks are fixed at the points 2 and 3 to the slur-cock rail I or a driving rod connected thereto by means of a friction-clutch. The driving chain 4 is laid around a plurality of sprocketwheels 5, 6, l, 8,9 and I; The sprocket-wheels and 6 are mounted on a'slide ll horizontally displaceable on the machine frame so that the portion of the chain 4 extending from the one inner sprocket-wheel 5 to the other inner sprocket-wheel 6 is directed perpendicularly to said slur-cock rail I. In a similar manner the sprocket-wheels I and 8 are mounted on a second slide I2 also horizontally displaceable on the machine frame, so that the portion of the chain 4 which is intermediate the sprocket-wheels I and B is likewise positioned perpendicular to the 1 rail l. The sprocket-wheel 9 is supported at the free end of a double-armed cranked lever l4 pivoted at l3 to the slide l2, as shown in Fig. 1. The longer arm l5 of the lever l4 carries a roller l6 engaging with a curved track I! fast on the machine 'frame, so that the sprocket-wheel 9 upon displacement of the slide l2 will be adjusted with respect to the latter. The curved track I1 should be of proper conformation to maintain the driving chain 4 in stretched condition during 20 every adjustment between the slides II and i2. The sprocket-wheel I0 is mounted on the slide l2.

The difference in the height of the sprocketwheels 5 and 8 is preferably chosen somewhat greater than the operating stroke ofthe slur-cock 25 rail I. The slides H and I2 are connected in known manner -with an adjusting device in such a way that the latter will determine the adjustment of said slides II and I2 and simultaneously therewith their distance from each other. 30

The portion of the driving chain 4 positioned between the sprocket-wheels 6 and 1 carries at its center in the known manner a pivot 20 carrying a sliding block 2|. The latter is'displaceable within a vertical guide 22 fixedly connected to the catch-bar 23 and through the latter detachably from the slur-cock rail I. A brake for the transmission of power from theslur-cock rail I to the bar 23 will not be necessary. It may, however, be preferable to provide for such trans- 40 mission of power a friction clutch which does not need to be exactly adjusted upon a definite amount of power to be transmitted as is the case when employing a brake, said friction clutch operating only if during the transmission of driving motion to the thread-carrier rail a fracture of some of the organs of the machine is liable to arise. The aforementioned friction clutch, however, should be used only in case such a clutch is not present between the slur-cock rail I and the driving rod.

As the portions of the driving chain positioned on the one hand between the sprocket-wheels 5 and 6 and on the other hand between the sprocket-wheels 'l and 8 are on different sides of the portion of said chain stretching between the sprocket-wheels 6 and 1, the slides II and I2 may be moved towards each other in such a manner that the chain 4 extends in a closed path from the sprocket-wheel 5 as far as to the sprocket-wheel 8. In order to ensure this, the sprocket-wheels 6 and I must be arranged to permit motion of one wheel past the other without any obstruction arising during adjusting the slides I I and I2 into shortest distance between each other. This maybe accomplished in a most convenient way by placing the sprocket-wheel I with its axis above the axis of the sprocketwheel 6, the distance between said two axes being equal to the sum of the outer diameters of said sprocket-wheels, in order to provide a free path of motion above the sprocket-wheel 6 for the sprocket-wheel I in the proper relative position of the slides II and I2, and in order to attain horizontal or approximately horizontal position of the portion of the chain 4 stretching between said sprocket-wheels 6 and I. If the sprocket-wheels 6 and 'I are equipped in this case 'with relatively widely projecting guide-disks or teeth, the driving chain 4 should be constructed with three tracks, the two outer tracks co-operating each with one set of sprocket-wheels 5, 1 and 8 and the middle track with the sprocketwheel 6. Upon moving the slides II and I2 towards each other the projecting teeth on the sprocket-wheel 6 will pass between the teeth on the two sprocket-wheels I. If, on the other hand, the sprocket-wheels 6 and I are not provided with properly projecting parts, or if the sprocketwheels I are positioned at a. proper height above the wheels 6, a chain with a single track and a single set of sprocket-wheels 5, 6, 1 and 8 may be used as shown in Fig. 3. In this case also a cable, rope, belt or the like may be used instead of the chain 4.

In many instances, and more particularly in case the portion of the chain 4 running from the sprocket-wheel 6 to the sprocket-wheel 1 is stretched out in exactly horizontal position and the roller 9 so arranged that said chain runs also in stretched condition from the wheel 8 to the wheel I0, the length of the curved track I! may be reduced to extend only through a short distance, said track now solely serving the purpose of keeping the chain 4 in stretched condition while the wheel I is moved above and past the wheel 6 in the respective position of the slides II and I2. This condition may also be attained by means of a fixed stop with which the arm I4 of the cranked lever I4, I5 comes into engagement at the proper time.

From the aforegiven explanation it follows that with a definite relative adjustment of the slides II and I2,-the guide 22 and the thread-carrier rail will be adjusted, upon each reciprocating motion of the slur-cock rail I or of the driving rod connected thereto, along the horizontal distance between the portion of the chain extending from the wheel 5 to the wheel 6 and the portion of the chain extending from the wheel I to the wheel 8. This is due to the fact that the slide block 2I is moving up and down idle within its guide 22. If, however, the pivot 20 is moving from the wheel 6 towards the wheel I or in opposite direction, said pivot will impart positive motion to the guide 22 and the thread-carrier rail connected thereto. If the two slides II and I2 are moved towards each other to an extent that the chain 4 reaches in stretched condition from the wheel 5 to the wheel 8, there will be no adjustment whatever of the guide 22 upon reciprocating motion of the slur-cock rail I. Thus, by adjusting the slides I I and I2 the adjustment of the guide 22 and of the guide block 2| therein may be reduced to an extent necessary for knitting the toe portion of a stocking, so that the aforedescribed operating mechanism will be practicable without the use of any kind of brakes, which had so far been regarded as being indispensable.

If nointrinsical value is placed on the possibility of reducing the stroke of the thread-carrier rail as far as to zero, a shortening of the path of driving motion of the respective thread-carrier rail may be attained in many cases in a better way, as compared with the known arrangement of rollers. For this purpose a double-tracked chain 4' as shown in Figs. 4 and 5 is carried over two co-axial sprocket-Wheels 5' on the slide II, thereupon only over one sprocket wheel 6' on the same slide and thereupon over the sprocketwheel I and two co-aixal sprocket-wheels 8, all three on the slide I2, the wheel 6' running in a track different from that for the wheel I, consequently permitting passage of one wheel past the other during moving together the slides, so that said wheels will finally come into co-axial position. In this case the diameter of the sprocket-wheels 6' and 1' must be chosen as small as possible.

Instead of keeping the chain 4 in stretched condition by a positive motion of the tension roller 8 whenever the sprocket-wheels 6 and I shown in Fig. 1 pass one above the other, it would also be possible, in order to attain the same result, to move upward and downward one or both slides II and I2 at the end of their path of motion obliquely to the direction of motion of the slur-cock rail I, eventually by means of a curved track. If the axes of the two sprocketwheels 6 and I have moved, one above and past the other, the portions of the chain, which had so far been on said wheels 6 and 1 will be stretched, and now the sum of those portions of the chain is increased that are freely stretched out between the fixed ends 2 and 3 of the chain, the portion of the chain that had previously been positioned between the wheels 6 and I having now come outside of said wheels. The infiuence of the first mentioned condition preponderates at the moment the axes of the sprocketwheels 6 and I are just in position one perpendicularly above the other. If the slides I I and I 2, however, are further moved towards each other the lengthening of the horizontal portion of the chain will be more and more noticeable. This change in the tension of the chain must be taken into consideration, when using a tension roller 9 for positive adjustment of the chain as well as when moving the slides II and'I2 in transverse direction.

As regards the special shape of the sprocket wheels 5, 6, I, 8, and 9 it may be remarked that these wheels may also be made more of acylindrical form, that is, in the form of a roller or the like.

Instead of the closed guide-member 22 as shown in Fig. 1 preferably a guide may be used that is open not only at its under end, as known, but also at its upper end, as shown in Fig. 6; in this case the catch-member made in the form of a guide-roller will move out of its open guide in upward or downward direction, whenever during reciprocating motion of. the chain 4 said roller comes in contact with a vertically directed site to the former. In this case the chain 4 which serves for the transmission of the driving motion from the slur-cock rail l to one of the thread-carrier rails is fastened in the abovementionedmanner on said slur-cock rail or on some other reciprocating organ-of the knitting machine. The catch-member 24 forming part of a thread-carrier is thus carried with the chain 4 along the portion positioned between the two vertical portions 25 and 26 extending in downward and upward direction, respectively,. and being positioned outside of the sprocket-wheels 6 and I. 1

About at the center point of the chain 4 there is provided a bolt or pivot 21 which is either fastened to a link of the chain 4 or made'in the form of an extension of a link pin of said chain.- Mounted on said bolt or link pin is a roller 28 and in order to drive the catch-member 24 from said roller 28 two vertical extensions of ledges 29 and 30 are arranged on the latter, the distance between said extensions or ledges being equal to the diameter of said roller 28. The space between said ledges 29 and 30 opens freely above and below, so that the roller 28 may immediately come out of the range of action of said ledges, as-

soon as it engages with one of the two portions of the chain directed perpendicularly to the catchmember 24. The roller 28 may also again enter freely the space between the ledges 28 and 30 as soon as during the subsequent working step the chain 4 again carries back the roller 28 into the range of action of said ledges. The roller 28 may therefore be made of small length, the centers of the ledges 29 and 30 being at even height with the portion of the chain between the rollers 6 and 1.

The ledges 29 and 311 are well rounded at their upper and under ends as shown in Fig. 6 to permit the roller 28 to always easily enter the space between said ledges.

The aforedescribed operating mechanism may not only be used for imparting motionto the carrier for the ground-thread and the carriers for the thread which serves to re-inforce the toe portion of a stocking, but also for the purpose of operating the carrier of the thread destined for making the heel flap. In the latter case the thread-carrier 3i which, for instance, serves to re-inforce the upper part of the heel 32 on the right-hand side of a stocking as well as the thread-carrier which on the same side of the stocking isto lay the thread for making the heel-part 33 must be adjusted only on the part A of the series of meshes between the lateral edges of the upper part of the heel and the heel proper, this adjustment being effected by means of the roller 28 and the chain 4. As theseparts A of the series of meshes are outside of the center-line of the fabric and outside of the nee dies, the slides carrying the rollers 6 and I must be correspondingly adjusted. The roller 28 is thus positively carried always a short distance along the portions 26 and 25 of said chain through a distance appropriately greater than said former distance, said roller coming in every case out of the range of action of the ledges 29 and 30. The carriers for the thread destined for re-inforcement of the left-hand upper heel and for making the left-hand part of the heel as well as the carrier 34 for the ground thread must be driven in a similar manner.

I claim:

1. Operating mechanism for the thread-carrier rails of flat framework knitting machines, said mechanism comprising a pair of slides adjustable with respect to each other, a plurality of sprocketwheels, said sprocket-wheelsbeing mounted in part on said one and in part on said other slide, a driving'chain laid round said sprocket-wheels permitting variation of the length of the effective portion of said chain intermediate said slides during adjustment of the latter relatively to each other, the inner sprocket-wheels on either of said slides being mounted at a height permitting free passage of said one inner sprocket-wheel on one slide past said inner sprocket-wheel on said other slide when adjusting said slides into shortest distance from each other.

2. Operating mechanism as specified by claim 1, having said inner sprocket-wheels mounted at a height permitting passage of said one inner sprocket-wheel on said one slide above and past the inner sprocket-wheel on said other slide, when adjusting said slides into their shortest distance from each other.

3. Operating mechanism as specified by claim 1, having said inner sprocket-wheels displaced with respect to each other to permit said inner sprocket-wheel on one slide to come into co-axial position with said inner sprocket-wheel on said other slide upon adjustment of said slides into their shortest distance from each other.

'4. Operating mechanism as specified'by claim 1, said mechanism including a slur-cock rail, said sprocket-wheels and said chain being arranged so that the two portions of said chain positioned perpendicularly to said slur-cock rail and defining standstill of the thread-carrier guide-rails are di- 5. Operating mechanism as specified by claim 1, said mechanism including a slur-cock rail, and adjusting means arranged to permit adjustment of at least one of said sprocket-wheels with respect to said slides obliquely to the direction of said slur-cock rail.

6. Operating mechanism as specified by claim 1, said mechanism including a slur-cock rail, and a curved track associated with at least one of said sprocket-wheels, said curved track arranged to permit adjustment of said sprocket-wheel with respect to said slides for regulating the tension of said chain.

7. Operating mechanism as specified by claim 1, said mechanism including a slur-cock rail, an adjusting lever, a curved track fixed to the frame of the machine and adapted to form a guide for at least one of said sprocket-wheels, said lever and said curved track adapted to permit adjustment of said sprocket-wheel with respect to the respective slide in accordance with the displacement of the latter.

'8. Operating mechanism as specified by claim 1, said mechanism including a guide open in upward and downward direction and inserted into the portion of said chain intermediate said inner sprocket-wheels, a catch in the form of a guideroller co-operative with said'guide, said catch adapted to come out of engagement with said guide, whenever said catch during reciprocating motion of said portion of said chain arrives at a vertically directed portion of the latter.

9. Operating mechanism for the thread-carrier rails of flat framework knitting machines,

justment of the latter relatively to each other, the inner wheels on either of said slides being mounted at a height permitting free passage of said one inner wheel on one slide past said inner wheel on said other slide when adjusting said 6 slides into shortest distance from each other.

ANTON LOIMANN. 

